Music theory device



FIG. 1 is a perspective view of the music theory device showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a side view of the music theory device of FIG. 2 as viewed from the right;

FIG. 5 is a side view of the music theory device of FIG. 2 as viewed from the left;

FIG. 6 is a top view of the music theory device of FIG. 2;

FIG. 7 is a bottom view of the music theory device of FIG. 2;

FIG. 8 is another front view thereof;

FIG. 9 is a cross-sectional view of the music theory device of FIG. 8 as viewed along line 9-9; and,

FIG. 10 is an enlarged view of the portion within the circled area of FIG. 9 which is identified as “10”. 

CLAIM The ornamental design for the music theory device, as shown and described. 